A novel plastic optical fiber (POF) power coupler is proposed, which is different from fused taper type and mixing rod POF couplers. Loss factors of this coupler are analyzed theoretically. This coupler is based on thermal feature of POF, the two ends of the coupler is composed of fused drawn tapered fiber and thermal contracted tapered fiber. It is characterized by its simple configuration and easy fabrication. Experimental results indicate that the performance can meet the requirement of short distance plastic optical fiber transmission networks.